STARBUCKS- "parking lot OWN3D"!

[dayofpain]

filter is actually awesome. even though it should be a maf system but thats another story.

hmmmm

must be the THREE FOOT DRIVESHAFT that increases drag by like 8%


hmmmmmmmm

nope im sure... thats it.

[sperry]

You don't think an intake isolated from the engine compartment wouldn't allow for some helpfully cooler air? Or would the cool air not matter so much 'cause the forced induction heats it up so much anyway? I'm thinking since it's not intercooled, every degree lower would be a big help.

[AtomicLabMonkey]

That looks like an unprotected driveshaft going across the engine compartment, jesus... How could this accident have been avoided...

And my guess would be the temperature rise from air in the engine bay vs. a fenderwell for example is negligible compared to the temperature rise from compression. Like maybe 10-15 degrees vs. 100-200 degrees... just pulled those numbers out of my a55, but temp. gain from compression is usually quite a bit. I could do some heat transfer calcs on it... well... no, never mind I don't feel like putting out that kind of effort.

[sperry]

Originally Posted by AtomicLabMonkey

That looks like an unprotected driveshaft going across the engine compartment, jesus... How could this accident have been avoided...

And my guess would be the temperature rise from air in the engine bay vs. a fenderwell for example is negligible compared to the temperature rise from compression. Like maybe 10-15 degrees vs. 100-200 degrees... just pulled those numbers out of my a55, but temp. gain from compression is usually quite a bit. I could do some heat transfer calcs on it... well... no, never mind I don't feel like putting out that kind of effort.

But w/o an intercooler, lowering the initial air temp is the only way to lower the charged temp... might as well get that initial air as close to ambient as possible, right? That charger's gonna get pretty hot, and will heat up that area of the engine bay pretty well... I'd rather be pulling my air from outside if possible. 'Course, I dunno how the Integ's arflow from thru the radiator is, so that area of the compartment might be pretty well cooled...

BTW: Austin, this pic's from the AMLS race at Seca... you've seen this car in person!

[tysonK]

damn i don't know enough about supercharger design to come up with a witty comment. I guess i'll just say that integra is Superlame.

,el tyson

[dayofpain]

Originally Posted by sperry

But w/o an intercooler, lowering the initial air temp is the only way to lower the charged temp... might as well get that initial air as close to ambient as possible, right? That charger's gonna get pretty hot, and will heat up that area of the engine bay pretty well... I'd rather be pulling my air from outside if possible. 'Course, I dunno how the Integ's arflow from thru the radiator is, so that area of the compartment might be pretty well cooled...

BTW: Austin, this pic's from the AMLS race at Seca... you've seen this car in person!

hmmm where to begin. first off every degree counts on a turbo but not so much a supercharger. yes the compression from a super raises temperature but nothing like a turbo. obviously. all the centrifugal superchargers i have felt you can touch the housing because they dont get very hot. roots blowers get alot hotter.

an intercooler on a supercharger is called an aftercooler. dont ask why, it makes no sense.

and the reason tht catastrophic driveshaft exists. is because honda thought they were fucking cool by spinning the motor backwards. so the intake is in the back and then they thought it would also be a good idea to put the drivebelt on the tight side of the compartment.

honda strikes again, fucking geniuses.

[ShawnS]

Originally Posted by dayofpain

hmmm where to begin. first off every degree counts on a turbo but not so much a supercharger.

That's because the supercharger is not being spun by the exhaust gases. Besides, the ambient air temp near the filter is not enough to really matter because the charger is spun on the engine's belts. The only heat source that really matters is the headers. The air being pushed by the charger is too fast for any significant heat soak.

With setup, there is no pressure drop after the charger, and this makes up for the drag caused by shaft.

Sorry if this post sounds incoheirent(sp?). Its pretty late.

[ShawnS]

Anyway back to the topic at hand.

I had fun

Sorry guys for leaving the resturant in such a rush. Duty calls you know....

[AtomicLabMonkey]

Originally Posted by dayofpain

yes the compression from a super raises temperature but nothing like a turbo. obviously. all the centrifugal superchargers i have felt you can touch the housing because they dont get very hot. roots blowers get alot hotter.

I think it just all depends on the particulars of the TC or SC setup. A centrifugal supercharger and centrifugal turbocharger both just have impellers in the intake airstream, they're just air pumps. Theoretically if they're the same diameter, blade count, and shape impeller and spun at the same speed, they should both impart the same amount of work into the system, hence the same amount of heat. With the two systems doing the same amount of work (pressurization/boost), the only extra heat I could see in a real turbo setup in an engine bay would be some heat conducted through the turbo casing and shaft from the hot exhaust side of the shaft. I bet if you stuck an air temperature gauge in the intake tube downstream of a similar SC and TC the temps would be similar. Different impeller setups pushing different amount of boost could be quite different. SC guys usually have lots of detonation problems because they don't inter/after cool the compressed air... their intake air temps are real hot and they try to compensate by just adding lots of fuel to make the mixture real rich and tuning the spark timing.. which works so-so.

[dayofpain]

you make it sound like the turbo only heats the air a few more degrees than a supercharger. thats a huge no. a turbo even in its effecientcy range will heat up intake charges at least 150 degrees. sometimes all the way up to 300+ degrees.

the cast iron headers are in direct contact. in direct contact with the uppipe. in direct contact with the turbo. which is a direct part of the intake stream.

lets put it this way. if i run my turbo hard; at night, and pull over. even though its ceramic coated and leaches heat very well. its "red hot" when you pop the hood. no supercharger gets that hott. ever.

this is an age old discussion. which is better. no real answer. just what you are going to use it for.

[sperry]

I was thinking the same way as LabMonkey... take X amount of air and compress it into Y volume and the temp will go up Z degrees, regardless how you're doing the compression.

However, the exhaust running thru the turbo is in the 700 to 1000 degree range, which heats the hell out of the turbo itself... that's gotta account for a lot of the intake charge temp. My guess is that a lot of SC guys see temp caused dets because they're running a SC on a fairly high compression motor already. I

'd bet a SC on a WRX instead of a turbo wouldn't need an aftercooler, since the WRX motor's designed for boost and the associated higher temps.

Okay, that last part's just a crazy guess.

[tysonK]

Did you guys recieve the new SCCA Magazine? It has a rather large WRX/other AWD cars artcile. There is even a sonic yellow on the Cover. WRX is taking over I guess. :wink: